Electro-optic modulator having ridge waveguide structure

A ridge waveguide structure includes a substrate having a top surface; a ridge structure protruding from the top surface; and a waveguide formed in the ridge structure and a shape of the waveguide is corresponding to a shape of the ridge structure; the ridge structure includes a Y-shaped input section and a Y-shaped output section, the Y-shaped input section includes a total input section, a first branch and a second branch, the first branch and the second branch are diverged from the total input section and converged into the Y-shaped output section. The relation also relates to an electro-optic modulator.